Patrick Semansky / AP

If Supreme Court Chief Justice John Roberts is truly concerned about preserving the Court’s legitimacy in American life, as he’s often suggested, Brett Kavanaugh has become his worst nightmare.

After Friday’s Senate Judiciary Committee session, Kavanaugh is facing a renewed FBI investigation into the sexual-assault charges against him from Christine Blasey Ford. But even if that inquiry fails to produce decisive evidence, and Senate Republicans push through his nomination, the tactics Kavanaugh has already employed to preserve his candidacy are bound to stoke Roberts’s greatest fear.

After Ford’s compelling testimony to the Senate on Thursday, Kavanaugh’s nomination seemed to falter. But the judge revived his prospects among Senate Republicans by delivering an unrestrained assault on committee Democrats and the rest of the political left, whom he accused of colluding to sink his nomination. Kavanaugh expressed more open partisanship in his angry diatribes than any other modern Supreme Court nominee. Senator Lindsey Graham of South Carolina quickly fed the blaze that Kavanaugh ignited with his own red-faced, finger-jabbing attack against Democrats. Each shifted the debate—from a question of the credibility of the competing accounts about the alleged assault to a test of tribal loyalty.

Kavanaugh’s behavior has irrevocably marked his possible tenure on the Court. With such a partisan route as his pathway, a Justice Kavanaugh would arrive at the Supreme Court as a patient zero, carrying a virus of illegitimacy to its decisions. Since Kavanaugh declared his hostility to the Democratic Party and the left so openly and with such ferocity, it has seemed inevitable that tens of millions of Americans will never see him as an impartial judge.

That would create a stark equation for Roberts, who must surely realize that much—perhaps most—of the nation would question the validity of every 5–4 party-line decision in which Kavanaugh would provide the deciding vote. In the past, fear of further eroding the Court’s legitimacy has provided a limited (though hardly uniform) check on Roberts’s willingness to force major decisions on party-line votes. But if the Senate confirms Kavanaugh, it will present Roberts with a justice whose every decision will be viewed through the lens of the partisan and tribal animosities he inflamed to defend his nomination.

Every time Roberts would lean on Kavanaugh to construct a majority, the chief justice could further erode the Court’s already eroding public confidence. Before the disputed Bush v. Gore decision, which ended the recount in the 2000 presidential election, about half of Americans routinely expressed a great deal of confidence in the Court, according to Gallup polling. That number has fallen to 40 percent or less since the mid-2000s; in the latest Gallup measurement, from June, just one-third of Democrats said they had faith in the Court, compared with about two-fifths of Republicans. In a separate Gallup measure of job approval, the share of Republicans who gave the Court positive marks (67 percent) was almost double the portion of Democrats (36 percent).   

No matter how his hearings unfolded, Kavanaugh’s nomination was destined to heighten the political storms around the Court. He would create an all-male, five-member, Republican-appointed majority that could control the Court until the 2030s; its oldest member, Clarence Thomas, is only 70. Kavanaugh was also chosen to create a more reliably conservative majority than was possible under Anthony Kennedy, who broke from his fellow GOP justices on some key issues (though less so in his final year).

The replacement of Kennedy with Kavanaugh was always a recipe for future conflict, because it would increase the likelihood of years of 5–4 party-line votes to reject liberal legal priorities, whether that’s voting rights, environmental regulation, balancing the rights of defendants and law enforcement, or preserving legal access to abortion. Adding to the tension, Kavanaugh’s record signals he could provide the decisive vote for the majority to block efforts at opening more employment and educational opportunities to minorities through affirmative action and other diversity programs, even as nonwhites become a majority among young people. Looming over his nomination, too, was Democratic bitterness at Republicans’ refusal to even consider Merrick Garland, the appellate-court judge whom former President Barack Obama nominated for a Supreme Court vacancy.

All of this was baked in no matter how Kavanaugh’s confirmation went. But his openly partisan attacks raised the stakes. Only a few weeks ago, at his initial confirmation hearing in early September, Kavanaugh had echoed Roberts’s own famous analogy in declaring that a Supreme Court justice must be an “umpire” who maintains his independence from all sides. On Thursday, Kavanaugh completely abandoned that pose, railing in barely contained fury at Democrats, the Clintons, and “left wing” activists. He insisted that opposition to him was not based on his record, or the serious charges leveled against him by Ford and other women, but was instead driven by resentment over Trump’s victory. Then he proceeded to interrupt and belittle Democratic senators during hours of questioning. In every possible way, he validated the portrait that critics had painted of him as a Republican operative in robes.

Graham brought these arguments to an even more incendiary pitch. With bristling ferocity, the senator explicitly portrayed the vote as a test of tribal loyalty. Looking at Flake, who had been seen as the one possible weak link in a chain of unified Republican determination on the Judiciary Committee, Graham declared that voting against Kavanaugh would reward indefensible Democratic tactics, or what he called “the most despicable thing that I have seen in my time in politics.”

In Graham’s formulation, the question was not whether senators found Ford believable—or even credible enough to prompt further investigation—but whether they were loyal to their side.

In this, Graham demonstrated how much of the GOP has internalized and accepted President Trump’s confrontational political strategy. The president has consolidated support from the elements of white America most uneasy about cultural, demographic, and economic change by encouraging them to think of themselves as a minority assailed by forces from above and below: racial minorities and immigrants threatening their jobs and security on one end, and elites disdainful of their cultural values on the other. The core of Trump’s strategy has been to rally one group of Americans (older, blue-collar, evangelical, and rural whites) by convincing them that they are under siege from another (minorities, immigrants, liberal elites), and that only he can protect their interests.

Division is not a by-product of that political vision; it is the animating engine. And it is that engine that Graham and Kavanaugh revved to preserve his nomination. Like Trump, Kavanaugh and Graham sought to consolidate and mobilize their tribe primarily by presenting everyone outside it as a malevolent threat to its values and interests. That succeeded enough to propel the nominee from committee, though not without the conditions Flake demanded.

Kavanaugh’s prospects are now again uncertain, though it’s also unclear whether the FBI, in a tight time frame, can provide conclusive answers to the allegations against him. But even if the Senate confirms Kavanaugh, his turn toward tribalism will follow him to the Court, like a stain on marble. The more he succeeds in the mission for which he was chosen—tilting the Court’s balance more reliably to the right—the more he will aggravate the animosities over his selection, and surface memories of the open partisan contempt he displayed during the process.

Depending on how the FBI inquiry plays out, it remains possible that Democrats, if they regain the House majority in November, will reopen the investigation into his behavior, and perhaps examine impeaching him if the evidence warrants. Kavanaugh even makes it more likely that Democrats will explore enlarging the Court’s membership—which Congress can do without a constitutional amendment—when they next regain unified control of the White House, House, and Senate. It’s only a short stroll from the Capitol to the Supreme Court. But if Kavanaugh eventually makes that walk this week, he will expose the latter to the virulent political fevers of the former, as surely as if he were a patient escaping from quarantine.

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